Dacia

Dacia was a barbarian kingdom whose borders included Romania, Moldova, Bulgaria, Serbia, Ukraine, Hungary, Slovakia, and Poland, flourishing from the 82 BC until 106 AD, when Trajan conquered the kingdom from the king Decebalus.

History
The Dacians were united by King Burebista in 82 BC, and the tribespeople formed the Kingdom of Dacia, who formed an alliance with the Kingdom of Scythia, a fellow barbarian kingdom. However, they were brought into warfare with the Kingdom of Thrace, a Hellenistic-Barbarian faction who invaded their territory, and they were defeated, with most of their lands conquered. However, they remained a formidable foe, and in 101 AD, Trajan started a series of campaigns that subdued them. Sarmizegetusa, their capital, was razed and the Roman Empire absorbed them.